﻿using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

namespace Knlght.Web.Infrastructure
{
    public static class WebHelper
    {
        /// <summary>
        /// 验证身份证是否正确 
        /// </summary> 
        public static bool CheckCardId(string str)
        {
            if (str.Length >= 17)
            {
                string number17 = str.Substring(0, 17);
                string number18 = str.Substring(17);
                string check = "10X98765432";
                int[] num = { 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 };
                int sum = 0;
                for (int i = 0; i < number17.Length; i++)
                {
                    sum += Convert.ToInt32(number17[i].ToString()) * num[i];
                }
                sum %= 11;
                if (number18.Equals(check[sum].ToString(), StringComparison.OrdinalIgnoreCase))
                {
                    return true;
                }
            }
            return false;
        }

        /// <summary>
        /// API上传图片
        /// </summary>
        public static string UploadImgForApi(HttpContent img, string path)
        {
            //if(img.Headers.ContentLength<=0)
            //{
            //    throw new Exception("流文件为空");
            //}

            //上传图片的物理路径
            string dirTempPath = System.Web.HttpContext.Current.Server.MapPath(path);

            //创建目录
            if (!System.IO.Directory.Exists(dirTempPath))
            {
                System.IO.Directory.CreateDirectory(dirTempPath);
            }

            if (img.Headers.ContentDisposition.FileName != null)
            {
                //保存图片
                var filename = img.Headers.ContentDisposition.FileName.Replace("\"", "");
                string fileExt = filename.Substring(filename.LastIndexOf('.'));
                var fileTypes = "gif,jpg,jpeg,png,bmp";
                if (String.IsNullOrEmpty(fileExt) || Array.IndexOf(fileTypes.Split(','), fileExt.Substring(1).ToLower()) == -1)
                {
                    throw new Exception("上传文件扩展名是不允许的扩展名。");
                }
                System.Threading.Thread.Sleep(100);     //睡眠100毫秒防止多线程文件名重复
                string newFileName = DateTime.Now.ToString("yyyyMMddHHmmss_ffff");
                var nFileName = dirTempPath + "\\" + newFileName + fileExt;
                var ms = img.ReadAsStreamAsync().Result;
                using (var br = new BinaryReader(ms))
                {
                    var data = br.ReadBytes((int)ms.Length);
                    File.WriteAllBytes(nFileName, data);
                }

                //生成缩略图
                MakeThumbnail(nFileName, nFileName.Replace(fileExt, "_" + fileExt), 150, 150, "W");

                nFileName = path + "/" + newFileName + fileExt;
                return nFileName;
            }
            throw new Exception("获取图片失败，请重新上传");
        }

        /// <summary> 
        /// 生成缩略图 
        /// </summary> 
        /// <param name="originalImagePath">源图路径（物理路径）</param> 
        /// <param name="thumbnailPath">缩略图路径（物理路径）</param> 
        /// <param name="width">缩略图宽度</param> 
        /// <param name="height">缩略图高度</param> 
        /// <param name="mode">生成缩略图的方式</param>     
        public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
        {
            Image originalImage = Image.FromFile(originalImagePath);

            int towidth = width;
            int toheight = height;

            int x = 0;
            int y = 0;
            int ow = originalImage.Width;
            int oh = originalImage.Height;

            switch (mode)
            {
                case "HW"://指定高宽缩放（可能变形）                 
                    break;
                case "W"://指定宽，高按比例                     
                    toheight = originalImage.Height * width / originalImage.Width;
                    break;
                case "H"://指定高，宽按比例 
                    towidth = originalImage.Width * height / originalImage.Height;
                    break;
                case "Cut"://指定高宽裁减（不变形）                 
                    if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
                    {
                        oh = originalImage.Height;
                        ow = originalImage.Height * towidth / toheight;
                        y = 0;
                        x = (originalImage.Width - ow) / 2;
                    }
                    else
                    {
                        ow = originalImage.Width;
                        oh = originalImage.Width * height / towidth;
                        x = 0;
                        y = (originalImage.Height - oh) / 2;
                    }
                    break;
                default:
                    break;
            }

            //新建一个bmp图片 
            Image bitmap = new System.Drawing.Bitmap(towidth, toheight);

            //新建一个画板 
            Graphics g = System.Drawing.Graphics.FromImage(bitmap);

            //设置高质量插值法 
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;

            //设置高质量,低速度呈现平滑程度 
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;

            //清空画布并以透明背景色填充 
            g.Clear(Color.Transparent);

            //在指定位置并且按指定大小绘制原图片的指定部分 
            g.DrawImage(originalImage, new Rectangle(0, 0, towidth, toheight),
                new Rectangle(x, y, ow, oh),
                GraphicsUnit.Pixel);

            try
            {
                //以jpg格式保存缩略图 
                bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
            }
            catch (System.Exception e)
            {
                throw e;
            }
            finally
            {
                originalImage.Dispose();
                bitmap.Dispose();
                g.Dispose();
            }
        }
    }
}
